In multicellular organisms, DNA methylation is an important epigenetic modifier. It occurs predominantly on cytosine residues and the occurrence of 5 methyl cytosine (5meC) in the dinucleotide CpG plays important roles in mammalian development. Methylation patterns vary between cell types and are altered in cancer. In order to better understand the role of methylation in health and disease, we propose creating improved reagents that will allow for the efficient and accurate identification of 5-methyl cytosine (5meC) residues in DNA. These reagents will enable the identification of 5meC sites with single-nucleotide precision and are compatible with a variety of high-throughput methods, including DNA sequencing, microarray analysis, and mass spectrometry, among others. PUBLIC HEALTH RELEVANCE: Alterations in methylation patterns have the potential to be sensitive and specific diagnostic markers. This proposal aims to develop novel technology to detect and assay methylation patterns. The technology may be useful in developing improved diagnostic and prognostic tests to aid in detecting and treating human disease. [unreadable] [unreadable] [unreadable]